1. Field of the Invention
This invention relates to control of the operating parameters of an internal combustion engine.
2. Prior Art
It is known to use various means to reduce the output of undesirable emission components from an internal combustion engine. Known techniques include using exhaust gas recirculation (EGR) wherein the exhaust gas from the output of an engine is taken and returned to the intake of the engine. Thus any unoxidized material in the exhaust can be oxidized by passing through the engine again and the temperature in the combustion cylinder is reduced because inert and oxidized material is introduced thereby reducing the volume of material which is oxidized.
It is also known to pump air into the exhaust gas stream to further facilitate oxidation of any remaining material in the exhaust gas stream. Such introduction of air into the exhaust manifold is typically referred to as secondary air injection.
It is known to operate both secondary air injection and the EGR system in an open loop fashion whereby certain engine operating conditions initiate and terminate operation of the EGR and secondary air injection. It would be desirable to have a more accurate way of controlling secondary air injection and EGR. These are some of the problems this invention overcomes.